This proposal links our knowledge of noradrenergic hypothalamic systems that control feeding behavior with hormonal systems located in the same brain area, that control adipose tissue. Hormones provide a mechanism by which feeding, a short term phenomenon, may influence obesity, a long term phenomenon. Insulin, because it is lipogenic, is particularly important. Of the many lipolytic hormones, growth hormone will be given particular attention because of recent evidence that implicates it in the phenomenon of gold-thioglucose induced obsesity. Second, its release is enhanced or inhibited in baboons, respectively, by the same noradrenergic treatments of hypothalamus, that we have shown, enhances or inhibits feeding behavior in rats. The thrust of the present proposal centers around the relationship between feeding and obesity. Our objectives are: 1) to study the effects of intrahypothalamically implanted neurochemicals on the parameters of feeding behavior, as monitored by computer, 24 hrs/day, 7 days a week. This will provide informtion on duration of drug action, rebound effects associated with the post-drug condition, and information on long term effects of such treatments on circadian rhythms; 2) to study the correlation between the effects of intrahypothalamically implanted drugs, feeding behavior and blood levels of insulin and growth hormone; 3) to study the effects of obese syndromes in mice and rats on the endogenous levels of catecholamines and indole amines, by fluorometric and histochemical fluorescent techniques; 4) to investigate the effects of various forms of obesity, that are known to alter hormone levels, on feeding and drug-induced changes in feeding.